A will made during a sea voyage, in the form prescribed by articles 988 et seq. shall be valid only so long as the testator dies on board or within six months after he has disembarked in a place where he has been able to make it again in the ordinary forms.
However, if the testator undertakes a new sea voyage before the expiry of this period, the will will be valid for the duration of this voyage and for a further period of six months after the testator is again disembarked.